Electric-arc lamp.



PATENTED SEPT. 8, 1908. R. E. LEVE.

ELECTRIC ARC LAMP.

APPLICATION FILED JAN. 22, 1908.

e Iva Kai/0 p? ROBERT E. vLEVE, OF NEW YORK, N. Y.

ELECTRIC-ARC LAMP.

Specification of Letters latent.

Patented Sept. 8, 19081 Application filed January'22, 1908. Serial No. 412,107.

To all whom it may concern:

Be it known that I, ROBERT E. Lnvn, a citizen of the United States, residing in New York, in the borough of Manhattan, county and State of New York, have invented certain new and useful Improvements in Electric-Arc Lamps, of which the following is a specification.

This invention relates to are lamps and more particularly to the feeding and separating mechanisms for the electrodes.

Applicant is aware that, prior to his invention, an electrode carriage has been gravity fed by means of clock work operating continuously to lower the carriage during the burning of the lamp. He is also aware that an electrode carriage has been gravity fed by the release of friction brake mechanism controlled by a shunt coil. He is also aware that convergent electrodes have been fed by the differential effect of shunt and series coils, where said differential effect operated throughout its entire range to vary the brake tension; and that said differential effect has been utilized in the same mechanism to vary the relative separation of the electrode'ends while atthe same time varying the brake tension. This statement is made so that a clear conception of applicants invention may be had.

In general the object of applicants invention is to improve the feeding and control of an arc lamp, to cheapen and to simplify its construction.

Applicant has found that feeding mechanism relying upon the mere release of a frio tion brake to control the lowering of its electrode carriage results in irregular or jerky feeding due probably friction between relativelymoving surfaces. To insure proper steady feeding, applicant has devised apparatus in which he causes an inertia governor, which may be in the form of a pendulum escapement, to operate in parallel with his friction brake. By this combination the sudden decrease in friction at the brake referred to when feeding starts is counteracted by the inertia governor until the controlling mechanism automatically acts to apply the proper pressure to the brake mechanlsm. Ap icant has also found it desirable normal y to maintain a fixed tension or pressureiir-the brake mechanism, which isnot varied throughout part of the-range of the differential effect of the shunt and series coils, While their differential effect throughto the great decrease in.

out its entire range is effective in controlling the relative se aration of the electrode ends. A further advantage is obtained by applicant in economy of construction by arranging his winding drum, brake sheave and esca ement wheel all on a single shaft.

urther advantages will be apparent from the following description and will be set.

forth in the claims.

An embodiment of applicants invention for purposes of illustration is shown in the accompanying drawings, which form a part of this application, in which like characters designate corresponding parts and in which Figure 1 is a front elevation; Fig. 2 is a side elevation with parts broken away; and Fig. 3 is a top plan with parts broken away.

Referring now more in detail to the drawings,A indicates a base of suitable size and configuration for supporting the feeding and controlling mechanism, part of which is mounted on the upstanding frame I) suitably.

secured to the base A.

Mounted on the base A are shunt and series coils which are shown respectively as solenoids C and D separately mounted. These coils are arranged so that their differential effect may be utilized and this is accomplished in applica'nts illustrative embodiment by linking the re .{Jective solenoid cores 0 and d to opposite ends of a lever frame E pivoted intermediate its ends by the shaft c to the frame I). By this mechanism the joint effect of the coils is mechanically differentiated although the differentiation may be accomplished electrically or magnetically in a manner Well known in connection with electro-magnetic devices.

Suitably secured to and dependent from the base A are two pairs of parallel guides f, f and g, g, the pairs 'of guides being dow wardly convergent as shown in Fig. 1. A

uide tube H is also suitably secured to the l iase A and de ends vertically in a central position. The ower ends of the parts f, f, g, g and H are suitably secured to the lower partition i and serve to sustain the same in position.

The electrode carriage illustrated in its entirety by J has an up and down movement and its various parts are guided by the parts g, g, H. In the embodiment illustrated the carriage J comprises a central follower part j embracing the tube H and freely sliding thereon. Laterally projecting arms k and Z are fixed t0 the follower j and project through suitable hearings in. two-other follower members m and n: The follower memberm is providedwith suitable bearings which may embrace the ways or guides f, f while the follower member n is similarly related to the ways or guides g, g. In an intermediate position between the ways f, f and Ways 9, g, the follower members m and n are respectively provided with securing means or clamps 0 and p for the electrodes g and 1'. The electrodes g and r extend down parallel to the ways f and g. The electrode q projecting through a suitable guide opening in the lower partition platei and the electrode ralso thrdugh an enlarged or slotted o ening in the plate 41, after first passing through a comparatively snuglyfitting opening in the adjustableslide s which will be described later.

Projectin into the interior of the tubeH from the follower membery' and through the slot h is a pin shown-in dotted lines in Fig. 1, and designated by't. To. this pin is secured suitable suspension means a servin to hold the entire carriage J and suspen ed electrodes g and r in suspension to be gravity fed and subject to' control as will hereinafter be apparent.

pon a main shaft o journaled in the frame I) is suitably arranged a collection of parts operative in the control of the feeding hereinbefore referred to A winding drum to is.

suitably positioned upon the shaft 1) and is fixed against feeding or unwinding rotationrelatively to the shaft 12. This method of securing may be that of a selfwinding drumand as shown in the drawings in which a ratchet wheel as is secured to the shaft 12 and a spring pressed pawl y, secured to the drum to engages the ratchet 0c permitting rotation to wind up cord at but preventiifg relative feeding rotation. A winding spring 2 is provided, one end of which is secured to the drum w and the other end of which-is secured to the frame I) and which has a tendency when the suspension means or cord at has been unwound from the drum 1!; to re-wind the drum to by reason of the tension placed in the spring z by the unwinding of the drum. For some purposes the drum w may be secured fast-fto the shaft 1;, as when the drum is not to be self-winding.

A brake sheave 2 is fixed fast to the shaft '0 and also an esca ement wheel 3 is fixed fast to the shaft '0. escapement 4, which may be pivoted to the frame I by the pivot 5, nominally engages the escapement wheel 3 and, as shown, may be provided with dependent pendulum like portions 6. This escapement wheel and escapement is aninertia governor by reason of the fact that, in order that a rotation of the escapement wheel 3 may take lace, it is necessary that escapement 4 with its pendulum be moved back and forth constantly overcoming the inertia may be efiected.

A suitable friction band 7 which maybe in the form of a cord or chain is provided for the brake sheave 2. "This friction band is held preferably under normal tension about the brake sheave 2 and is under the control of the shunt coil 0, as well as under the control of the differential effect of the shunt coil 0 and the series coil D throughout a certain part of the range of said differential effect as will hereinafter be apparent. To insure normal fixed tension of the band 7 about the sheave 2,"one end of the band 7 may be secured to the crossbar 8 of the frame I; and the a other end secured to one. end of a lever 9 fulcrumed upon a shaft 10 journaled in the frame I). To the other end of the lever 9, is secured a tension spring-11 adjustably secured at one end by the screw 12 to. the base A. A lever arm 18 is also secured to the shaft 10 and extends out towards the shunt coil C as indicated in the drawings. Suitably mounted on the frame E is an adjustable screw 14 which passes through the crosspiece 15 of the frame E, and is ositioned so as to overlie the free end of the ever 13. In Fig. 1, the end of the screw 14 is shown just touching the end of the-lever 13, and it is obvious that after a downward movement of the solenoid core (1 an upward movement of the screw 14 would be accom lished and there would be no effect upon t e lever 13, and conse uently none upon the tension of the brake hand 7. However, should the efseries coil D and cause a downward movement of the core c,'-the screw 14 would press against the free end of the lever 13, moving it against the tension of s ring 11 to decrease the tension of the bra e band 7 about the brake sheave 2. This brake tension 10' feet of the shunt coil C overcome that of the would be varied throughout the limits of the differential effect of the coils O and D'measured by the movement of the end of the screw 14 from the position shown in Fig. 1 to the lowermost osition for the end of screw 14 which the dlfferential efiect of the coils C and D could bring about, but not throughout any other portion of this diflerential effect, since an upward movement 'of screw 14 can never increase the brake tension above normal.

As shown the entire weight of the electrode carriage and electrodes is resisted by the feeding mechanism but by reason of the peculiar brake control and the inertia governor operating in parallel thereto -very steady feeding is accomplished. In addition to this control of the feeding as described, the differential effect of the coils C and D is harnessed so as to regulate or control the relative separation of the arcing ends of the electrodes 9 and 1' by mechanism as follows:-

of the moving parts before the rotation of the l Pivoted to the lever frame E, as by the stud 15, is a connecting rod 16 passing down through the hole 17 in base A and pivoted at its lower end to one end of the bell crank lever 18-. The bell crank lever 18 may be journaled to the upright 19 fixed to partition the separation of the electrode ends is va,

ried throughout the entire range of the difl'erential eiiect of coils U and. D. When the series coil 1) overcomes shunt coil G the electrodes are separated and vice versa. 23 indicates a bridge of suitable material between the electrodes.

it is to be understood that the electric circuit connections for the coils and the electrodes, etc, may be in accordance with well known practice in the art and need not be described in detail; also necessary insulation and other well known. accessories may be embodied in the construction, such as suitable resistance, connecting wires, blow out magnet indicated by 24 etc.

Certain of the parts of my invention are useful in other combinations than those illustrated and may be modified in their embodiment all within the scope of the accompanying claims.

hat 1 claim and desire to secure by Letters Patent is 1. In an arc lamp, a suspended gravityrotatable shaft; a brake .band fixed at one end and normally held under fixed tension about said brake sheave; means for adjusting said fixed tension; a shunt and a series coil; provisions for dili'ercntiating the joint efiect of said coils; means intermediate said provisions andsaid brake band for decreasing said brake tension throughout only a part of the range of the dii'l'ercntial effect of said coils; an escapement cooperating with said escapementwheel; and means intermediate said provisions and said electrodes for changing the relative lateral separation of the electrode ends throughout the range of said differential efl'ect of said coils.

2v In an arc lamp, asusp'ended gravity feed electrode carriage sustaining a pair of depcndeng converging electrodes; feeding mechanism for said carriage com rising a winding drum for a suspension cor a brake sheave and an escapement wheel all mounted concentrically upon and secured to a single rotatable shaft; a brake-band fixed at one end and normally held under fixed tension about said brake sheave; means for adjusting said fixed tension; a shunt and a series coil; provisions for differentiating the joint effect ofvsaid coils; adjustable means intermediate said provisions and said brake band for decreasing said brake tension throu hout only a part of the range of the differential effect of said coils; an escapement cooperating with said escapement wheel; and means intermediate said provisions and said electrodes for changing the relative lateral separation of the electrode ends throughout the range of said differential effect of said coils.

In testimony, that I claim the foregoing as my invention, 1 have signed my name in presence of two subscribing witnesses.

ROBERT ELEVE. Witnesses PAUL GoEPEL;

H NRY J. SUHRBIER. 

